This is interesting and it’s obvious that it works. One way to defeat this attack is to store cryptographics keys in a storage which loses all its content after power off. A hard problem.
Cold boot disk encryption attack is shockingly effective – Engadget
Schneier on Security: Cold Boot Attacks Against Disk Encryption
Center for Information Technology Policy » Lest We Remember: Cold Boot Attacks on Encryption Keys
Edited to add: Read an (german) interview with Ed Felton in TR — the CS professor behind those attacks. Here the original blog post: Freedom to Tinker » Blog Archive » New Research Result: Cold Boot Attacks on Disk Encryption
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